(FYI this would be best suited for General ROM Hacking). Since SM64 Ds is a 3d game, it uses 3D models for levels. So to make custom levels you need to create a 3D model for the game to load. If you’re just starting in 3D modeling, I would suggest using Sketchup 8 (a 3D modeling tool).

Best of luck to you
~Ndymario
_________________________I'm the only person on this board that hacked MvL before it was cool.

I recommend avoiding sketchup since it's a very weak tool and teaches you bad habits. I recommend learning blender, which is free. It takes a bit more work to learn over sketchup but it's far more worth it.
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I recommend avoiding sketchup since it's a very weak tool and teaches you bad habits. I recommend learning blender, which is free. It takes a bit more work to learn over sketchup but it's far more worth it.

sorry for the late response, but yeah I'll try blender. I used Sketchup and man does it lack many functions!